1. Field of the Invention
The present invention pertains to polyalkylenepolyamine polyethers. More particularly, the present invention pertains to processes for the preparation of such polyethers. Even more particularly, the present invention concerns processes for the preparation of such polyethers by the reaction of an alkylenepolyamine and an epihalohydrin.
2. Prior Art
The preparation of condensation products by the reaction of an amine and an epihalohydrin is well documented in the prior art. Within this broad class of compounds numerous sub-classes have been denoted. Thus, the reaction of alkylamines and epihalohydrins has been documented numerous times.
Generally, this latter sub-class of compounds have been developed to enhance the properties of paper, to provide improved drainage aids and so forth.
As the art has developed, there has been an increasing amount of activity toward the development of polyalkylenepolyamine polyethers as wet and dry strength paper additives; drainage aids; flocculants and the like. Furthermore, such compounds often define intermediate for the preparation of other compounds, such as surfactants, ion exchange resins and the like. In preparing such polyethers, normally, an alkylamine is reacted with a polyhalohydrin under controlled conditions. The controlled conditions are necessary in order to preclude and prevent cross-linking of the reactants. Cross-linking provides a water-insoluble, gelled mass which is of substantially no utility. On the other hand, control of the reaction conditions provides water-soluble highly useful compounds.
Within the context of controlling the reaction conditions, the art has taught maintaining a strict molar ratio minimum. Falling below the minimum results in highly cross-linked products. The art, also, teaches control of temperatures and reaction times.
In U.S. Pat. No. 3,746,678, there is taught the reaction of ethylene diamine and polyepichlorohydrin. The reference specifically discloses that at least about three moles of polyamine be reacted per chlorine atom in the chlorinated alkylene oxide polymer. The reference further teaches that using a ratio of less than 3:1 is an inoperable procedure.
As will subsequently be detailed, the present invention provides a process whereby ratios of less than 3:1 can be utilized to prepare non-gelled polyalkylene polyamine polyethers by the reaction of an alkylamine and a polyhalohydrin.